问题
选择题
已知元素的原子序数，可以推断原子的（ ）
①质子数； ②中子数； ③最外层电子数； ④核电荷数； ⑤核外电子总数； ⑥相对原子质量．
A．①③④⑤
B．①②④⑤
C．①④⑤⑥
D．①②③⑤
答案
已知元素的原子序数，由原子中，质子数=原子序数=核电荷数=核外电子数，
则可推断①③④⑤，
故选A．
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已知元素的原子序数，可以推断原子的（ ）
①质子数； ②中子数； ③最外层电子数； ④核电荷数； ⑤核外电子总数； ⑥相对原子质量．
A．①③④⑤
B．①②④⑤
C．①④⑤⑥
D．①②③⑤
已知元素的原子序数，由原子中，质子数=原子序数=核电荷数=核外电子数，
则可推断①③④⑤，
故选A．
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